textproduct: Albany

WHAT HAS CHANGED

Pockets of freezing rain confined to the southern Adirondacks region this morning before temps rise above freezing. Patchy freezing drizzle persists until daybreak for western New England higher terrain. Patchy fog added to the forecast until the late morning for portions of the forecast area.

Slight chance of thunderstorms expanded from the Capital Region west and southwest today into tonight ahead of cold front.

KEY MESSAGES

1) Patchy freezing drizzle/pockets of freezing rain this morning across portions of western New England and the southern Adirondacks before temps rise above freezing.

2) Warm-up this weekend with some isolated to widely scattered thunderstorms today into tonight coupled with some snow melt.

3) An extended period of above normal temperatures expected early to mid week. The anomalous warmth with chances of rainfall increasing late Tue through the mid week will aid in snow melt, potential river rises, and a subsequent threat of ice jams/minor flooding.

DISCUSSION

KEY MESSAGE 1... A short-wave continues to move towards and across the region this morning, as a warm front is lifting north/northeast from the Mid Atlantic Region. Abundant low-level moisture is in place with low clouds, some patchy fog and spotty drizzle/freezing drizzle over portions of western New England. A few slick spots may occur on untreated roads this morning. High pressure is moving downstream of Nova Scotia, but is still funneling some shallow cool/cold air across portions of western New England. The 00Z KALY sounding shows a strong low-level inversion below H850 with the moisture trapped. Early this morning, some showers are popping up over w-central NY and the Tug Hill Plateau. This is due to the low to mid-level warm advection. Isolated to scattered showers will increase for locations along and northwest of the Capital Region. A brief period or pockets of freezing rain will be possible in the southern Adirondacks or near the east/southeast foothills. We will expand the current SPS,if this materializes, though the latest NYS Mesonet observations temps at or above freezing. The Showalter values dip below 0C with some elevated instability, so a rumble or two of thunder may graze the southwest Adirondacks this morning.

The warm front attempts to clear at least portions of the forecast area by the late pm. However, the deeper low-level moisture and clouds will be tough to clear, except maybe locations west/southwest of the Capital Region over the western Mohawk and Schoharie Valleys as well as the eastern Catskills, where the widely scattered thunderstorm threat is possible late this afternoon and into tonight. Will discuss that in the next key point. Nonetheless, in the pseudo warm sector temps will run above normal for early March with highs in the mid 40s to lower 50s. Some mid and upper 50s are possible west/southwest of Albany with breezy southeast to south winds. Some snow melt will occur with a couple ft rises, but the latest NERFC forecast indicates no flooding and within banks rises, though predicting ice break-up and movement will be challenging without 3 feet or more rises.

KEY MESSAGE 2... Some widely scattered/isolated non-severe thunderstorms are anticipated from the Capital Region west/southwest late this afternoon into tonight. The strong low-level inversion or stable layer will inhibit strong winds from reaching the sfc from aloft. Potential stronger convection that may impact west- central NY will be in a weakening stage based on the CAMS. Most if not all the instability will be elevated with MUCAPEs less than 500 J/kg. Mid-level lapse rates will be marginal at 6-6.5C/km, but some small hail or graupel may occur. SPC has general thunderstorms for eastern NY and western New England today-tonight in their Day 1 Outlook. This aligns with WFO ALY thinking. PWATs do rise to an inch or greater, so some localized brief bursts of rain may occur. However, total QPF today through tonight will be mainly a tenth to a third of an inch with perhaps a third of an inch to an inch for the western Mohawk Valley and southwest Adirondacks, though their is a deep snowpack of 1-3 feet in these locations, which should absorb the rainfall. Lows fall into the mid and upper 30s north and west of the Capital Region with lower to mid 40s for the rest of the areas, as the cold front moves through tonight.

KEY MESSAGE 3... The isolated to scattered showers end from the Capital Region south and east Sunday morning, as the cold front moves through. Temps will close the weekend above normal, but cold advection will be occurring across the region. Due to downsloping and a warm start, max temps will reach the upper 40s to upper 50s in the valleys and the Capital Region south and east with upper 30s to upper 40s over the higher terrain. Some additional run off is possible, but it should slow with colder temps expected Sunday night with high pressure building in from the Ohio Valley Sunday night with lows in the upper 20s to mid 30s.

The mid and upper level flow is zonal to open the week, but then H500/mid level heights increase 1-2 STDEVs above normal based on the NAEFS heading into Tue with above normal temps increasing. H850 temps will also run a few STDEVS above normal. A mild day is expected on Mon with highs in the 50s to lower 60s with a few mid 60s in the mid Hudson Valley. Above normal low temps in the 30s and lower 40s are forecasted based on the NBM Mon night. The warmest day of the week looks like Tue with widespread 50s to mid 60s (15-20 degrees above normal) with even some upper 60s to around 70F readings near I84. Substantial snow melt will occur with some ice breakup possible. Some of the latest MMEFS (NAEFS/GEFS) and HEFS ensemble hydrograph guidance show some low chances for minor flooding at a few points (i.e. the Housatonic Basin) based on the snow melt. It is typically is challenging to get flooding just on snow melt, but some ice breakup and movement may agitate a few basins.

A slow moving cold front increases the chances of rainfall Tue night through the mid week. The runoff+snow melt could pose a few problems. Therefore, we will continue to closely monitor trends in the case that these conditions could pose a threat with ice jams and subsequent flooding. We will continue to closely monitor how ice levels in the HSA rivers/streams have been impacted by these warmer temps. Cooler temps return Thu- Fri with some snow or rain/snow chances depend on the placement of the front and waves moving along it, though a lot of uncertainty exists in the ensembles and medium range guidance late next week.

AVIATION /06Z SATURDAY THROUGH WEDNESDAY/

A fluctuation of conditions begins the TAF period due to low cloud ceilings in IFR/MVFR conditions. IFR conditions should remain in place due to low ceilings between 08z and 12z. Then, IFR ceilings should continue throughout the TAF period. Some patchy fog/mist could occur around sunrise this morning bringing visibilities down to 3 to 5 miles included in TEMPO groups, but confidence was low to include mention at KALB due to the low cloud ceilings continuing into this morning. For tonight (after 00z), rain showers begin to move in with higher confidence at KGFL, KPSF, and KALB to include light shower activity mention in the prevailing between 00z and 06z.

Winds increase later this morning through this afternoon between 5 and 15 knots with gusts between 15 and 20 knots. For KPSF, started earlier for LLWS at 2 kft between 12z and 18z for winds around 35 knots. After 08/00z, LLWS between 35 and 45 knots at 2 kft has been introduced for all TAF sites. Breezy winds continue through the end of the TAF period.

Outlook...

Sunday Night to Tuesday: No Operational Impact. NO SIG WX. Tuesday Night: Moderate Operational Impact. Chance of RA. Wednesday: High Operational Impact. Definite RA.

ALY WATCHES/WARNINGS/ADVISORIES

CT...None. NY...None. MA...None. VT...None.